Pulmonary Artery Hypertension in Formerly Premature Infants With Bronchopulmonary Dysplasia: Clinical Features and Outcomes in the Surfactant Era

• Published in: Pediatrics (Evanston) Vol. 120; no. 6; pp. 1260 - 1269
• Main Authors: Khemani, Ekta, McElhinney, Doff B, Rhein, Lawrence, Andrade, Olyn, Lacro, Ronald V, Thomas, Kristin C, Mullen, Mary P
• Format: Journal Article
• Language: English
• Published: Elk Grove Village, IL Am Acad Pediatrics 01-12-2007; American Academy of Pediatrics
• Subjects: Babies; Biological and medical sciences; Bronchopulmonary dysplasia; Bronchopulmonary Dysplasia - complications; Bronchopulmonary Dysplasia - drug therapy; Care and treatment; Demographic aspects; Diagnosis; Female; General aspects; Humans; Hypertension; Hypertension, Pulmonary - diagnosis; Hypertension, Pulmonary - etiology; Hypertension, Pulmonary - mortality; Infant; Infant, Newborn; Infant, Premature, Diseases; Infants (Premature); Male; Medical sciences; Nitric oxide; Patient outcomes; Pediatrics; Physiological aspects; Pneumology; Premature birth; Premature infants; Pulmonary hypertension; Pulmonary hypertension. Acute cor pulmonale. Pulmonary embolism. Pulmonary vascular diseases; Pulmonary surfactant; Pulmonary surfactants; Respiratory diseases; Respiratory system : syndromes and miscellaneous diseases; Risk factors; Surface-Active Agents - therapeutic use; Survival analysis; United States; Premature; Pediatrics; Prognosis; Cardiovascular disease; Infant; chronic lung disease; Intracardiac defect; Surfactant; pulmonary vascular disease; Vascular disease; Pulmonary vessel; Pulmonary surfactant; Heart disease; Blood vessel; Atrial septal defect; Bronchus disease; Evolution; Human; Lung disease; Respiratory disease; Chronic disease; Clinical form; Congenital disease; Pulmonary artery; Pulmonary hypertension; Symptomatology; Newborn diseases; Chronic; Prematurity; Malformation; Bronchopulmonary dysplasia; Circulatory system
• ISSN: 0031-4005; 1098-4275
• DOI: 10.1542/peds.2007-0971

Although abnormal pulmonary vascular structure and function in preterm infants with bronchopulmonary dysplasia may predispose infants to pulmonary artery hypertension, little is known about the characteristics and outcomes of bronchopulmonary dysplasia-associated pulmonary artery hypertension in the surfactant era.
We studied 42 premature infants (< 32 weeks of gestation) with bronchopulmonary dysplasia who were diagnosed as having pulmonary artery hypertension > or = 2 months after birth, between 1998 and 2006, at a median age of 4.8 months. Pulmonary artery hypertension was graded through echocardiography for all patients; 13 patients also underwent cardiac catheterization.
Eighteen (43%) of 42 patients had severe pulmonary artery hypertension (systemic or suprasystemic right ventricular pressure). Among 13 patients who underwent catheterization, the mean pulmonary artery pressure was 43 +/- 8 mmHg and the pulmonary vascular resistance index was 9.9 +/- 2.8 Wood units. In 12 patients, pulmonary artery pressure and pulmonary vascular resistance improved with 100% oxygen and 80 ppm inhaled nitric oxide but remained elevated. The pulmonary vascular resistance index decreased to 7.9 +/- 3.8 Wood units in 100% oxygen and to 6.4 +/- 3.1 Wood units with the addition of nitric oxide. Sixteen patients (38%) died during the follow-up period. Estimated survival rates were 64% +/- 8% at 6 months and 53% +/- 11% at 2 years after diagnosis of pulmonary artery hypertension. In multivariate analyses, severe pulmonary artery hypertension and small birth weight for gestational age were associated with worse survival rates. Among 26 survivors (median follow-up period: 9.8 months), pulmonary artery hypertension was improved, relative to its most severe level, in 24 patients (89%).
Premature infants with bronchopulmonary dysplasia and severe pulmonary artery hypertension are at high risk of death, particularly during the first 6 months after diagnosis of pulmonary artery hypertension.